aboutsummaryrefslogtreecommitdiff
path: root/src/interfaces/libpq/fe-auth.c
Commit message (Collapse)AuthorAge
* Avoid core dump after getpwuid_r failure.Tom Lane2024-09-08
| | | | | | | | Looking up a nonexistent user ID would lead to a null pointer dereference. That's unlikely to happen here, but perhaps not impossible. Thinko in commit 4d5111b3f, noticed by Coverity.
* More use of getpwuid_r() directlyPeter Eisentraut2024-09-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove src/port/user.c, call getpwuid_r() directly. This reduces some complexity and allows better control of the error behavior. For example, the old code would in some circumstances silently truncate the result string, or produce error message strings that the caller wouldn't use. src/port/user.c used to be called src/port/thread.c and contained various portability complications to support thread-safety. These are all obsolete, and all but the user-lookup functions have already been removed. This patch completes this by also removing the user-lookup functions. Also convert src/backend/libpq/auth.c to use getpwuid_r() for thread-safety. Originally, I tried to be overly correct by using sysconf(_SC_GETPW_R_SIZE_MAX) to get the buffer size for getpwuid_r(), but that doesn't work on FreeBSD. All the OS where I could find the source code internally use 1024 as the suggested buffer size, so I just ended up hardcoding that. The previous code used BUFSIZ, which is an unrelated constant from stdio.h, so its use seemed inappropriate. Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi> Discussion: https://www.postgresql.org/message-id/flat/5f293da9-ceb4-4937-8e52-82c25db8e4d3%40eisentraut.org
* libpq: Trace all messages received from the serverAlvaro Herrera2024-08-16
| | | | | | | | | | | | | | | | | | Not all messages that libpq received from the server would be sent through our message tracing logic. This commit tries to fix that by introducing a new function pqParseDone which make it harder to forget about doing so. The messages that we now newly send through our tracing logic are: - CopyData (received by COPY TO STDOUT) - Authentication requests - NegotiateProtocolVersion - Some ErrorResponse messages during connection startup - ReadyForQuery when received after a FunctionCall message Author: Jelte Fennema-Nio <postgres@jeltef.nl> Discussion: https://postgr.es/m/CAGECzQSoPHtZ4xe0raJ6FYSEiPPS+YWXBhOGo+Y1YecLgknF3g@mail.gmail.com
* libpq: Trace frontend authentication challengesAlvaro Herrera2024-08-12
| | | | | | | | | | | | | | | | | | If tracing was enabled during connection startup, these messages would previously be listed in the trace output as something like this: F 54 Unknown message: 70 mismatched message length: consumed 4, expected 54 With this commit their type and contents are now correctly listed: F 36 StartupMessage 3 0 "user" "foo" "database" "alvherre" F 54 SASLInitialResponse "SCRAM-SHA-256" 32 'n,,n=,r=nq5zEPR/VREHEpOAZzH8Rujm' F 108 SASLResponse 'c=biws,r=nq5zEPR/VREHEpOAZzH8RujmVtWZDQ8glcrvy9OMNw7ZqFUn,p=BBwAKe0WjSvigB6RsmmArAC+hwucLeuwJrR5C/HQD5M=' Author: Jelte Fennema-Nio <postgres@jeltef.nl> Reviewed-by: Michael Paquier <michael@paquier.xyz> Discussion: https://postgr.es/m/CAGECzQSoPHtZ4xe0raJ6FYSEiPPS+YWXBhOGo+Y1YecLgknF3g@mail.gmail.com
* Use PqMsg_* macros in fe-auth.c.Nathan Bossart2024-06-26
| | | | | | | | Commit f4b54e1ed9, which introduced macros for protocol characters, missed updating a few places in fe-auth.c. Author: Jelte Fennema-Nio Discussion: https://postgr.es/m/CAGECzQSoPHtZ4xe0raJ6FYSEiPPS%2BYWXBhOGo%2BY1YecLgknF3g%40mail.gmail.com
* Revise GUC names quoting in messages againPeter Eisentraut2024-05-17
| | | | | | | | | | | | | | | After further review, we want to move in the direction of always quoting GUC names in error messages, rather than the previous (PG16) wildly mixed practice or the intermittent (mid-PG17) idea of doing this depending on how possibly confusing the GUC name is. This commit applies appropriate quotes to (almost?) all mentions of GUC names in error messages. It partially supersedes a243569bf65 and 8d9978a7176, which had moved things a bit in the opposite direction but which then were abandoned in a partial state. Author: Peter Smith <smithpb2250@gmail.com> Discussion: https://www.postgresql.org/message-id/flat/CAHut%2BPv-kSN8SkxSdoHano_wPubqcg5789ejhCDZAcLFceBR-w%40mail.gmail.com
* Explicitly require password for SCRAM exchangeDaniel Gustafsson2024-03-21
| | | | | | | | | | | | | | This refactors the SASL init flow to set password_needed on the two SCRAM exchanges currently supported. The code already required this but was set up in such a way that all SASL exchanges required using a password, a restriction which may not hold for all exchanges (the example at hand being the proposed OAuthbearer exchange). This was extracted from a larger patchset to introduce OAuthBearer authentication and authorization. Author: Jacob Champion <jacob.champion@enterprisedb.com> Discussion: https://postgr.es/m/d1b467a78e0e36ed85a09adf979d04cf124a9d4b.camel@vmware.com
* Refactor SASL exchange to return tri-state statusDaniel Gustafsson2024-03-21
| | | | | | | | | | | | | | The SASL exchange callback returned state in to output variables: done and success. This refactors that logic by introducing a new return variable of type SASLStatus which makes the code easier to read and understand, and prepares for future SASL exchanges which operate asynchronously. This was extracted from a larger patchset to introduce OAuthBearer authentication and authorization. Author: Jacob Champion <jacob.champion@enterprisedb.com> Discussion: https://postgr.es/m/d1b467a78e0e36ed85a09adf979d04cf124a9d4b.camel@vmware.com
* Add new function, PQchangePassword(), to libpqJoe Conway2024-01-09
| | | | | | | | | | | | | | | | | | | | | | | | | | Essentially this moves the non-interactive part of psql's "\password" command into an exported client function. The password is not sent to the server in cleartext because it is "encrypted" (in the case of scram and md5 it is actually hashed, but we have called these encrypted passwords for a long time now) on the client side. This is good because it ensures the cleartext password is never known by the server, and therefore won't end up in logs, pg_stat displays, etc. In other words, it exists for the same reason as PQencryptPasswordConn(), but is more convenient as it both builds and runs the "ALTER USER" command for you. PQchangePassword() uses PQencryptPasswordConn() to do the password encryption. PQencryptPasswordConn() is passed a NULL for the algorithm argument, hence encryption is done according to the server's password_encryption setting. Also modify the psql client to use the new function. That provides a builtin test case. Ultimately drivers built on top of libpq should expose this function and its use should be generally encouraged over doing ALTER USER directly for password changes. Author: Joe Conway Reviewed-by: Tom Lane Discussion: https://postgr.es/m/flat/b75955f7-e8cc-4bbd-817f-ef536bacbe93%40joeconway.com
* Update copyright for 2024Bruce Momjian2024-01-03
| | | | | | | | Reported-by: Michael Paquier Discussion: https://postgr.es/m/ZZKTDPxBBMt3C0J9@paquier.xyz Backpatch-through: 12
* Introduce macros for protocol characters.Nathan Bossart2023-08-22
| | | | | | | | | | | This commit introduces descriptively-named macros for the identifiers used in wire protocol messages. These new macros are placed in a new header file so that they can be easily used by third-party code. Author: Dave Cramer Reviewed-by: Alvaro Herrera, Tatsuo Ishii, Peter Smith, Robert Haas, Tom Lane, Peter Eisentraut, Michael Paquier Discussion: https://postgr.es/m/CADK3HHKbBmK-PKf1bPNFoMC%2BoBt%2BpD9PH8h5nvmBQskEHm-Ehw%40mail.gmail.com
* Include <limits.h> in fe-auth.c, to get CHAR_BIT reliably.Tom Lane2023-07-17
| | | | | | | | | | | | | fe-auth.c references CHAR_BIT since commit 3a465cc67, but it did not #include <limits.h>, which per POSIX is where that symbol is defined. This escaped notice so far because (a) on most platforms, <sys/param.h> pulls in <limits.h>, (b) even if yours doesn't, OpenSSL pulls it in, so compiling with --with-openssl masks the omission. Per bug #18026 from Marcel Hofstetter. Back-patch to v16. Discussion: https://postgr.es/m/18026-d5bb69f79cd16203@postgresql.org
* Remove obsolete comment and code from fe-auth.c.Thomas Munro2023-07-09
| | | | | | | | | | We don't use getpwuid() anymore (see commit e757cdd6), so we don't need locking around pg_get_user_name(). Reviewed-by: Andres Freund <andres@anarazel.de> Reviewed-by: Peter Eisentraut <peter@eisentraut.org> Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi> Discussion: https://postgr.es/m/CA%2BhUKGLtmexrpMtxBRLCVePqV_dtWG-ZsEbyPrYc%2BNBB2TkNsw%40mail.gmail.com
* Remove support for OpenSSL 1.0.1Michael Paquier2023-07-03
| | | | | | | | | | | | | | Here are some notes about this change: - As X509_get_signature_nid() should always exist (OpenSSL and LibreSSL), hence HAVE_X509_GET_SIGNATURE_NID is now gone. - OPENSSL_API_COMPAT is bumped to 0x10002000L. - One comment related to 1.0.1e introduced by 74242c2 is removed. Upstream OpenSSL still provides long-term support for 1.0.2 in a closed fashion, so removing it is out of scope for a few years, at least. Reviewed-by: Jacob Champion, Daniel Gustafsson Discussion: https://postgr.es/m/ZG3JNursG69dz1lr@paquier.xyz
* Spell the values of libpq's gssdelegation parameter as "0" and "1".Tom Lane2023-05-22
| | | | | | | | | | | | | That's how other boolean options are handled, so do likewise. The previous coding with "enable" and "disable" was seemingly modeled on gssencmode, but that's a three-way flag. While at it, add PGGSSDELEGATION to the set of environment variables cleared by pg_regress and Utils.pm. Abhijit Menon-Sen, per gripe from Alvaro Herrera Discussion: https://postgr.es/m/20230522091609.nlyuu4nolhycqs2p@alvherre.pgsql
* Expand some more uses of "deleg" to "delegation" or "delegated".Tom Lane2023-05-21
| | | | | | | | | | Complete the task begun in 9c0a0e2ed: we don't want to use the abbreviation "deleg" for GSS delegation in any user-visible places. (For consistency, this also changes most internal uses too.) Abhijit Menon-Sen and Tom Lane Discussion: https://postgr.es/m/949048.1684639317@sss.pgh.pa.us
* libpq: Error message improvementPeter Eisentraut2023-05-16
|
* De-Revert "Add support for Kerberos credential delegation"Stephen Frost2023-04-13
| | | | | | | | | | | | | | | | | | This reverts commit 3d03b24c3 (Revert Add support for Kerberos credential delegation) which was committed on the grounds of concern about portability, but on further review and discussion, it's clear that we are better off explicitly requiring MIT Kerberos as that appears to be the only GSSAPI library currently that's under proper maintenance and ongoing development. The API used for storing credentials was added to MIT Kerberos over a decade ago while for the other libraries which appear to be mainly based on Heimdal, which exists explicitly to be a re-implementation of MIT Kerberos, the API never made it to a released version (even though it was added to the Heimdal git repo over 5 years ago..). This post-feature-freeze change was approved by the RMT. Discussion: https://postgr.es/m/ZDDO6jaESKaBgej0%40tamriel.snowman.net
* Revert "Add support for Kerberos credential delegation"Stephen Frost2023-04-08
| | | | | | | | | | | This reverts commit 3d4fa227bce4294ce1cc214b4a9d3b7caa3f0454. Per discussion and buildfarm, this depends on APIs that seem to not be available on at least one platform (NetBSD). Should be certainly possible to rework to be optional on that platform if necessary but bit late for that at this point. Discussion: https://postgr.es/m/3286097.1680922218@sss.pgh.pa.us
* Add support for Kerberos credential delegationStephen Frost2023-04-07
| | | | | | | | | | | | | | | | | | | Support GSSAPI/Kerberos credentials being delegated to the server by a client. With this, a user authenticating to PostgreSQL using Kerberos (GSSAPI) credentials can choose to delegate their credentials to the PostgreSQL server (which can choose to accept them, or not), allowing the server to then use those delegated credentials to connect to another service, such as with postgres_fdw or dblink or theoretically any other service which is able to be authenticated using Kerberos. Both postgres_fdw and dblink are changed to allow non-superuser password-less connections but only when GSSAPI credentials have been delegated to the server by the client and GSSAPI is used to authenticate to the remote system. Authors: Stephen Frost, Peifeng Qiu Reviewed-By: David Christensen Discussion: https://postgr.es/m/CO1PR05MB8023CC2CB575E0FAAD7DF4F8A8E29@CO1PR05MB8023.namprd05.prod.outlook.com
* Make SCRAM iteration count configurableDaniel Gustafsson2023-03-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace the hardcoded value with a GUC such that the iteration count can be raised in order to increase protection against brute-force attacks. The hardcoded value for SCRAM iteration count was defined to be 4096, which is taken from RFC 7677, so set the default for the GUC to 4096 to match. In RFC 7677 the recommendation is at least 15000 iterations but 4096 is listed as a SHOULD requirement given that it's estimated to yield a 0.5s processing time on a mobile handset of the time of RFC writing (late 2015). Raising the iteration count of SCRAM will make stored passwords more resilient to brute-force attacks at a higher computational cost during connection establishment. Lowering the count will reduce computational overhead during connections at the tradeoff of reducing strength against brute-force attacks. There are however platforms where even a modest iteration count yields a too high computational overhead, with weaker password encryption schemes chosen as a result. In these situations, SCRAM with a very low iteration count still gives benefits over weaker schemes like md5, so we allow the iteration count to be set to one at the low end. The new GUC is intentionally generically named such that it can be made to support future SCRAM standards should they emerge. At that point the value can be made into key:value pairs with an undefined key as a default which will be backwards compatible with this. Reviewed-by: Michael Paquier <michael@paquier.xyz> Reviewed-by: Jonathan S. Katz <jkatz@postgresql.org> Discussion: https://postgr.es/m/F72E7BC7-189F-4B17-BF47-9735EB72C364@yesql.se
* libpq: Add sslcertmode option to control client certificatesMichael Paquier2023-03-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The sslcertmode option controls whether the server is allowed and/or required to request a certificate from the client. There are three modes: - "allow" is the default and follows the current behavior, where a configured client certificate is sent if the server requests one (via one of its default locations or sslcert). With the current implementation, will happen whenever TLS is negotiated. - "disable" causes the client to refuse to send a client certificate even if sslcert is configured or if a client certificate is available in one of its default locations. - "require" causes the client to fail if a client certificate is never sent and the server opens a connection anyway. This doesn't add any additional security, since there is no guarantee that the server is validating the certificate correctly, but it may helpful to troubleshoot more complicated TLS setups. sslcertmode=require requires SSL_CTX_set_cert_cb(), available since OpenSSL 1.0.2. Note that LibreSSL does not include it. Using a connection parameter different than require_auth has come up as the simplest design because certificate authentication does not rely directly on any of the AUTH_REQ_* codes, and one may want to require a certificate to be sent in combination of a given authentication method, like SCRAM-SHA-256. TAP tests are added in src/test/ssl/, some of them relying on sslinfo to check if a certificate has been set. These are compatible across all the versions of OpenSSL supported on HEAD (currently down to 1.0.1). Author: Jacob Champion Reviewed-by: Aleksander Alekseev, Peter Eisentraut, David G. Johnston, Michael Paquier Discussion: https://postgr.es/m/9e5a8ccddb8355ea9fa4b75a1e3a9edc88a70cd3.camel@vmware.com
* libpq: Remove code for SCM credential authenticationMichael Paquier2023-03-17
| | | | | | | | | | | | | | | | | | | | Support for SCM credential authentication has been removed in the backend in 9.1, and libpq has kept some code to handle it for compatibility. Commit be4585b, that did the cleanup of the backend code, has done so because the code was not really portable originally. And, as there are likely little chances that this is used these days, this removes the remaining code from libpq. An error will now be raised by libpq if attempting to connect to a server that returns AUTH_REQ_SCM_CREDS, instead. References to SCM credential authentication are removed from the protocol documentation. This removes some meson and configure checks. Author: Michael Paquier Reviewed-by: Tom Lane Discussion: https://postgr.es/m/ZBLH8a4otfqgd6Kn@paquier.xyz
* libpq: Add support for require_auth to control authorized auth methodsMichael Paquier2023-03-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The new connection parameter require_auth allows a libpq client to define a list of comma-separated acceptable authentication types for use with the server. There is no negotiation: if the server does not present one of the allowed authentication requests, the connection attempt done by the client fails. The following keywords can be defined in the list: - password, for AUTH_REQ_PASSWORD. - md5, for AUTH_REQ_MD5. - gss, for AUTH_REQ_GSS[_CONT]. - sspi, for AUTH_REQ_SSPI and AUTH_REQ_GSS_CONT. - scram-sha-256, for AUTH_REQ_SASL[_CONT|_FIN]. - creds, for AUTH_REQ_SCM_CREDS (perhaps this should be removed entirely now). - none, to control unauthenticated connections. All the methods that can be defined in the list can be negated, like "!password", in which case the server must NOT use the listed authentication type. The special method "none" allows/disallows the use of unauthenticated connections (but it does not govern transport-level authentication via TLS or GSSAPI). Internally, the patch logic is tied to check_expected_areq(), that was used for channel_binding, ensuring that an incoming request is compatible with conn->require_auth. It also introduces a new flag, conn->client_finished_auth, which is set by various authentication routines when the client side of the handshake is finished. This signals to check_expected_areq() that an AUTH_REQ_OK from the server is expected, and allows the client to complain if the server bypasses authentication entirely, with for example the reception of a too-early AUTH_REQ_OK message. Regression tests are added in authentication TAP tests for all the keywords supported (except "creds", because it is around only for compatibility reasons). A new TAP script has been added for SSPI, as there was no script dedicated to it yet. It relies on SSPI being the default authentication method on Windows, as set by pg_regress. Author: Jacob Champion Reviewed-by: Peter Eisentraut, David G. Johnston, Michael Paquier Discussion: https://postgr.es/m/9e5a8ccddb8355ea9fa4b75a1e3a9edc88a70cd3.camel@vmware.com
* Run pgindent on libpq's fe-auth.c, fe-auth-scram.c and fe-connect.cMichael Paquier2023-03-09
| | | | | | | | | A patch sent by Jacob Champion has been touching this area of the code, and the set of changes done in a9e9a9f has made a run of pgindent on these files a bit annoying to handle. So let's clean up a bit the area, first, to ease the work on follow-up patches. Discussion: https://postgr.es/m/9e5a8ccddb8355ea9fa4b75a1e3a9edc88a70cd3.camel@vmware.com
* Update copyright for 2023Bruce Momjian2023-01-02
| | | | Backpatch-through: 11
* libpq error message refactoring, part 2Peter Eisentraut2022-11-15
| | | | | | | This applies the new APIs to the code. Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org> Discussion: https://www.postgresql.org/message-id/flat/7c0232ef-7b44-68db-599d-b327d0640a77@enterprisedb.com
* Remove redundant null pointer checks before free()Peter Eisentraut2022-07-03
| | | | | | | | | | Per applicable standards, free() with a null pointer is a no-op. Systems that don't observe that are ancient and no longer relevant. Some PostgreSQL code already required this behavior, so this change does not introduce any new requirements, just makes the code more consistent. Discussion: https://www.postgresql.org/message-id/flat/dac5d2d0-98f5-94d9-8e69-46da2413593d%40enterprisedb.com
* Pre-beta mechanical code beautification.Tom Lane2022-05-12
| | | | | Run pgindent, pgperltidy, and reformat-dat-files. I manually fixed a couple of comments that pgindent uglified.
* Rearrange libpq's error reporting to avoid duplicated error text.Tom Lane2022-02-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit ffa2e4670, libpq accumulates text in conn->errorMessage across a whole query cycle. In some situations, we may report more than one error event within a cycle: the easiest case to reach is where we report a FATAL error message from the server, and then a bit later we detect loss of connection. Since, historically, each error PGresult bears the entire content of conn->errorMessage, this results in duplication of the FATAL message in any output that concatenates the contents of the PGresults. Accumulation in errorMessage still seems like a good idea, especially in view of the number of places that did ad-hoc error concatenation before ffa2e4670. So to fix this, let's track how much of conn->errorMessage has been read out into error PGresults, and only include new text in later PGresults. The tricky part of that is to be sure that we never discard an error PGresult once made (else we'd risk dropping some text, a problem much worse than duplication). While libpq formerly did that in some code paths, a little bit of rearrangement lets us postpone making an error PGresult at all until we are about to return it. A side benefit of that postponement is that it now becomes practical to return a dummy static PGresult in cases where we hit out-of-memory while trying to manufacture an error PGresult. This eliminates the admittedly-very-rare case where we'd return NULL from PQgetResult, indicating successful query completion, even though what actually happened was an OOM failure. Discussion: https://postgr.es/m/ab4288f8-be5c-57fb-2400-e3e857f53e46@enterprisedb.com
* Improve error handling of HMAC computationsMichael Paquier2022-01-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This is similar to b69aba7, except that this completes the work for HMAC with a new routine called pg_hmac_error() that would provide more context about the type of error that happened during a HMAC computation: - The fallback HMAC implementation in hmac.c relies on cryptohashes, so in some code paths it is necessary to return back the error generated by cryptohashes. - For the OpenSSL implementation (hmac_openssl.c), the logic is very similar to cryptohash_openssl.c, where the error context comes from OpenSSL if one of its internal routines failed, with different error codes if something internal to hmac_openssl.c failed or was incorrect. Any in-core code paths that use the centralized HMAC interface are related to SCRAM, for errors that are unlikely going to happen, with only SHA-256. It would be possible to see errors when computing some HMACs with MD5 for example and OpenSSL FIPS enabled, and this commit would help in reporting the correct errors but nothing in core uses that. So, at the end, no backpatch to v14 is done, at least for now. Errors in SCRAM related to the computation of the server key, stored key, etc. need to pass down the potential error context string across more layers of their respective call stacks for the frontend and the backend, so each surrounding routine is adapted for this purpose. Reviewed-by: Sergey Shinderuk Discussion: https://postgr.es/m/Yd0N9tSAIIkFd+qi@paquier.xyz
* Clean up messy API for src/port/thread.c.Tom Lane2022-01-11
| | | | | | | | | | | | | | | | | | | | | | | The point of this patch is to reduce inclusion spam by not needing to #include <netdb.h> or <pwd.h> in port.h (which is read by every compile in our tree). To do that, we must remove port.h's declarations of pqGetpwuid and pqGethostbyname. pqGethostbyname is only used, and is only ever likely to be used, in src/port/getaddrinfo.c --- which isn't even built on most platforms, making pqGethostbyname dead code for most people. Hence, deal with that by just moving it into getaddrinfo.c. To clean up pqGetpwuid, invent a couple of simple wrapper functions with less-messy APIs. This allows removing some duplicate error-handling code, too. In passing, remove thread.c from the MSVC build, since it contains nothing we use on Windows. Noted while working on 376ce3e40. Discussion: https://postgr.es/m/1634252654444.90107@mit.edu
* Clean up error message reported after \password encryption failure.Tom Lane2022-01-11
| | | | | | | | | | | | | | | Experimenting with FIPS mode enabled, I saw regression=# \password joe Enter new password for user "joe": Enter it again: could not encrypt password: disabled for FIPS out of memory because PQencryptPasswordConn was still of the opinion that "out of memory" is always appropriate to print. Minor oversight in b69aba745. Like that one, back-patch to v14.
* Improve error handling of cryptohash computationsMichael Paquier2022-01-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The existing cryptohash facility was causing problems in some code paths related to MD5 (frontend and backend) that relied on the fact that the only type of error that could happen would be an OOM, as the MD5 implementation used in PostgreSQL ~13 (the in-core implementation is used when compiling with or without OpenSSL in those older versions), could fail only under this circumstance. The new cryptohash facilities can fail for reasons other than OOMs, like attempting MD5 when FIPS is enabled (upstream OpenSSL allows that up to 1.0.2, Fedora and Photon patch OpenSSL 1.1.1 to allow that), so this would cause incorrect reports to show up. This commit extends the cryptohash APIs so as callers of those routines can fetch more context when an error happens, by using a new routine called pg_cryptohash_error(). The error states are stored within each implementation's internal context data, so as it is possible to extend the logic depending on what's suited for an implementation. The default implementation requires few error states, but OpenSSL could report various issues depending on its internal state so more is needed in cryptohash_openssl.c, and the code is shaped so as we are always able to grab the necessary information. The core code is changed to adapt to the new error routine, painting more "const" across the call stack where the static errors are stored, particularly in authentication code paths on variables that provide log details. This way, any future changes would warn if attempting to free these strings. The MD5 authentication code was also a bit blurry about the handling of "logdetail" (LOG sent to the postmaster), so improve the comments related that, while on it. The origin of the problem is 87ae969, that introduced the centralized cryptohash facility. Extra changes are done for pgcrypto in v14 for the non-OpenSSL code path to cope with the improvements done by this commit. Reported-by: Michael Mühlbeyer Author: Michael Paquier Reviewed-by: Tom Lane Discussion: https://postgr.es/m/89B7F072-5BBE-4C92-903E-D83E865D9367@trivadis.com Backpatch-through: 14
* Update copyright for 2022Bruce Momjian2022-01-07
| | | | Backpatch-through: 10
* Add more sanity checks in SASL exchangesMichael Paquier2021-07-10
| | | | | | | | | | | | | | | | | | | | | | The following checks are added, to make the SASL infrastructure more aware of defects when implementing new mechanisms: - Detect that no output is generated by a mechanism if an exchange fails in the backend, failing if there is a message waiting to be sent. - Handle zero-length messages in the frontend. The backend handles that already, and SCRAM would complain if sending empty messages as this is not authorized for this mechanism, but other mechanisms may want this capability (the SASL specification allows that). - Make sure that a mechanism generates a message in the middle of the exchange in the frontend. SCRAM, as implemented, respects all these requirements already, and the recent refactoring of SASL done in 9fd8557 helps in documenting that in a cleaner way. Analyzed-by: Jacob Champion Author: Michael Paquier Reviewed-by: Jacob Champion Discussion: https://postgr.es/m/3d2a6f5d50e741117d6baf83eb67ebf1a8a35a11.camel@vmware.com
* Refactor SASL code with a generic interface for its mechanismsMichael Paquier2021-07-07
| | | | | | | | | | | | | | | | | | | | | | The code of SCRAM and SASL have been tightly linked together since SCRAM exists in the core code, making hard to apprehend the addition of new SASL mechanisms, but these are by design different facilities, with SCRAM being an option for SASL. This refactors the code related to both so as the backend and the frontend use a set of callbacks for SASL mechanisms, documenting while on it what is expected by anybody adding a new SASL mechanism. The separation between both layers is neat, using two sets of callbacks for the frontend and the backend to mark the frontier between both facilities. The shape of the callbacks is now directly inspired from the routines used by SCRAM, so the code change is straight-forward, and the SASL code is moved into its own set of files. These will likely change depending on how and if new SASL mechanisms get added in the future. Author: Jacob Champion Reviewed-by: Michael Paquier Discussion: https://postgr.es/m/3d2a6f5d50e741117d6baf83eb67ebf1a8a35a11.camel@vmware.com
* Remove server and libpq support for old FE/BE protocol version 2.Heikki Linnakangas2021-03-04
| | | | | | | | | | | | | | | | | Protocol version 3 was introduced in PostgreSQL 7.4. There shouldn't be many clients or servers left out there without version 3 support. But as a courtesy, I kept just enough of the old protocol support that we can still send the "unsupported protocol version" error in v2 format, so that old clients can display the message properly. Likewise, libpq still understands v2 ErrorResponse messages when establishing a connection. The impetus to do this now is that I'm working on a patch to COPY FROM, to always prefetch some data. We cannot do that safely with the old protocol, because it requires parsing the input one byte at a time to detect the end-of-copy marker. Reviewed-by: Tom Lane, Alvaro Herrera, John Naylor Discussion: https://www.postgresql.org/message-id/9ec25819-0a8a-d51a-17dc-4150bb3cca3b%40iki.fi
* In libpq, always append new error messages to conn->errorMessage.Tom Lane2021-01-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously, we had an undisciplined mish-mash of printfPQExpBuffer and appendPQExpBuffer calls to report errors within libpq. This commit establishes a uniform rule that appendPQExpBuffer[Str] should be used. conn->errorMessage is reset only at the start of an application request, and then accumulates messages till we're done. We can remove no less than three different ad-hoc mechanisms that were used to get the effect of concatenation of error messages within a sequence of operations. Although this makes things quite a bit cleaner conceptually, the main reason to do it is to make the world safer for the multiple-target-host feature that was added awhile back. Previously, there were many cases in which an error occurring during an individual host connection attempt would wipe out the record of what had happened during previous attempts. (The reporting is still inadequate, in that it can be hard to tell which host got the failure, but that seems like a matter for a separate commit.) Currently, lo_import and lo_export contain exceptions to the "never use printfPQExpBuffer" rule. If we changed them, we'd risk reporting an incidental lo_close failure before the actual read or write failure, which would be confusing, not least because lo_close happened after the main failure. We could improve this by inventing an internal version of lo_close that doesn't reset the errorMessage; but we'd also need a version of PQfn() that does that, and it didn't quite seem worth the trouble for now. Discussion: https://postgr.es/m/BN6PR05MB3492948E4FD76C156E747E8BC9160@BN6PR05MB3492.namprd05.prod.outlook.com
* Update copyright for 2021Bruce Momjian2021-01-02
| | | | Backpatch-through: 9.5
* Fix capitalization of messages, per style guidePeter Eisentraut2020-05-05
|
* Update copyrights for 2020Bruce Momjian2020-01-01
| | | | Backpatch-through: update all files in master, backpatch legal files through 9.4
* Make the order of the header file includes consistent in non-backend modules.Amit Kapila2019-10-25
| | | | | | | | | | | | Similar to commit 7e735035f2, this commit makes the order of header file inclusion consistent for non-backend modules. In passing, fix the case where we were using angle brackets (<>) for the local module includes instead of quotes (""). Author: Vignesh C Reviewed-by: Amit Kapila Discussion: https://postgr.es/m/CALDaNm2Sznv8RR6Ex-iJO6xAdsxgWhCoETkaYX=+9DW3q0QCfA@mail.gmail.com
* Fix use of term "verifier"Peter Eisentraut2019-10-12
| | | | | | | | | | | Within the context of SCRAM, "verifier" has a specific meaning in the protocol, per RFCs. The existing code used "verifier" differently, to mean whatever is or would be stored in pg_auth.rolpassword. Fix this by using the term "secret" for this, following RFC 5803. Reviewed-by: Michael Paquier <michael@paquier.xyz> Discussion: https://www.postgresql.org/message-id/flat/be397b06-6e4b-ba71-c7fb-54cae84a7e18%402ndquadrant.com
* Fix confusing error caused by connection parameter channel_bindingMichael Paquier2019-10-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When using a client compiled without channel binding support (linking to OpenSSL 1.0.1 or older) to connect to a server which supports channel binding (linking to OpenSSL 1.0.2 or newer), libpq would generate a confusing error message with channel_binding=require for an SSL connection, where the server sends back SCRAM-SHA-256-PLUS: "channel binding is required, but server did not offer an authentication method that supports channel binding." This is confusing because the server did send a SASL mechanism able to support channel binding, but libpq was not able to detect that properly. The situation can be summarized as followed for the case described in the previous paragraph for the SASL mechanisms used with the various modes of channel_binding: 1) Client supports channel binding. 1-1) channel_binding = disable => OK, with SCRAM-SHA-256. 1-2) channel_binding = prefer => OK, with SCRAM-SHA-256-PLUS. 1-3) channel_binding = require => OK, with SCRAM-SHA-256-PLUS. 2) Client does not support channel binding. 2-1) channel_binding = disable => OK, with SCRAM-SHA-256. 2-2) channel_binding = prefer => OK, with SCRAM-SHA-256. 2-3) channel_binding = require => failure with new error message, instead of the confusing one. This commit updates case 2-3 to generate a better error message. Note that the SSL TAP tests are not impacted as it is not possible to test with mixed versions of OpenSSL for the backend and libpq. Reported-by: Tom Lane Author: Michael Paquier Reviewed-by: Jeff Davis, Tom Lane Discussion: https://postgr.es/m/24857.1569775891@sss.pgh.pa.us
* Fix bogus order of error checks in new channel_binding code.Tom Lane2019-09-29
| | | | | | Coverity pointed out that it's pretty silly to check for a null pointer after we've already dereferenced the pointer. To fix, just swap the order of the two error checks. Oversight in commit d6e612f83.
* Add libpq parameter 'channel_binding'.Jeff Davis2019-09-23
| | | | | | | | | Allow clients to require channel binding to enhance security against untrusted servers. Author: Jeff Davis Reviewed-by: Michael Paquier Discussion: https://postgr.es/m/227015d8417f2b4fef03f8966dbfa5cbcc4f44da.camel%40j-davis.com
* Fix many typos and inconsistenciesMichael Paquier2019-07-01
| | | | | Author: Alexander Lakhin Discussion: https://postgr.es/m/af27d1b3-a128-9d62-46e0-88f424397f44@gmail.com
* Fix collection of typos and grammar mistakes in docs and commentsMichael Paquier2019-04-19
| | | | | Author: Justin Pryzby Discussion: https://postgr.es/m/20190330224333.GQ5815@telsasoft.com
* GSSAPI encryption supportStephen Frost2019-04-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On both the frontend and backend, prepare for GSSAPI encryption support by moving common code for error handling into a separate file. Fix a TODO for handling multiple status messages in the process. Eliminate the OIDs, which have not been needed for some time. Add frontend and backend encryption support functions. Keep the context initiation for authentication-only separate on both the frontend and backend in order to avoid concerns about changing the requested flags to include encryption support. In postmaster, pull GSSAPI authorization checking into a shared function. Also share the initiator name between the encryption and non-encryption codepaths. For HBA, add "hostgssenc" and "hostnogssenc" entries that behave similarly to their SSL counterparts. "hostgssenc" requires either "gss", "trust", or "reject" for its authentication. Similarly, add a "gssencmode" parameter to libpq. Supported values are "disable", "require", and "prefer". Notably, negotiation will only be attempted if credentials can be acquired. Move credential acquisition into its own function to support this behavior. Add a simple pg_stat_gssapi view similar to pg_stat_ssl, for monitoring if GSSAPI authentication was used, what principal was used, and if encryption is being used on the connection. Finally, add documentation for everything new, and update existing documentation on connection security. Thanks to Michael Paquier for the Windows fixes. Author: Robbie Harwood, with changes to the read/write functions by me. Reviewed in various forms and at different times by: Michael Paquier, Andres Freund, David Steele. Discussion: https://www.postgresql.org/message-id/flat/jlg1tgq1ktm.fsf@thriss.redhat.com